Update README
Experimental: occasionally gather profiling data to minimize memory overhead
Profiling: make larger call numbers easier to read
Experimental: improved profiling MAD accuracy over stat merges
Revert "Experimental: improved profiling MAD accuracy over stat merges"

Unnecessarily complex - the naive approach is simpler + produces results
that are sufficiently accurate in most cases.

This reverts commit 6f8795fcb8dc1c2f2e50c4f74afa7f9e256b7ef8.
Profiling stats housekeeping
Bump dependencies